Sheet mounting device



2 1942. R. J. WISE E 2,302,327

SHEET MOUNTING DEVICE Filed May 6, 1941 FER l IINVENTORS R. J. WISE R. D. PAR ROTT Patented Nov. 24, 1942 UNITED STATES PATENT OFFICE SHEET MOUNTING DEVICE Application May 6, 1941, Serial No. 392,052

7 Claims.

Thisinvention relates to elastic gripping bands or rings and more particularly to elastic annular helices adapted for holding transmitting and recording blanks to the revolving drums of facsimile and similar apparatus.

In facsimile transmitting and recording it is customary to employ a revolving cylinder about which the transmitting and recording blank is in some cases wrapped and secured in place by one or more annular wire helices. The scanning operation is eiiected by producing relative longitudinal movement between the revolving cylinder and the transmitting beam or recording stylus. In order to maintain the blank in close contact with the drum at the transmitting or recording position, the elastic helix is moved along the drum closely adjacent to the transmitting or recording position. This movement is efiected by rolling the annular helix along the drum. It is highly important, particularly in recording by means of a stylus contacting with the paper for passing electrical current therethrough, that the recording blank make firm contact with the drum throughout its entire circumference at the point of engagement of the stylus therewith. Heretofore, in forming the spiral springs employed for this purpose, it has been the practice to secure the ends of the spiral spring by forming each end into a hook and hooking the ends together to produce an endless structure. While this type of construction has been used successfully, it has the objection that it produces a gap between the convolutions adjacent the hooked ends so that no contact with the paper is made over this portion of the annulus. Moreover, the connection between the ends is not as rigid as is desirable for the proper rolling motion of the spiral along the blank.

An object of this invention is to provide a device of the type set forth having an improved construction for connecting the ends thereof together.

A further object is to provide a connecting device constructed and arranged to connect the ends of a spiral spring together in such a way as to provide a substantially continuous, unbroken surface to the band.

These and other objects which will be apparent to those skilled in the art are accomplished by the present invention, one embodiment of which is illustrated in the accompanying drawing, in which:

Fig. 1 is a perspective view of a spiral spring and connector for the ends thereof, disconnected from each other and illustrating one embodiment of the invention;

Fig. 2 is an elevation of the spring shown in Fig. 1 after the ends have been connected to- 7 gether;

Fig. 3 is a section through a joint between the spring ends illustrating another embodiment of the invention; and

Fig. 4 is a fragmentary view of a facsimile transmitter-recorder showing a cylinder and a blank secured thereon by the retaining ring shown in Figs. 1 and 2.

As illustrated in Figs. 1 and 2, a spiral spring ll formed by a closely wound wire helix has the ends l2 and 13 of the wire terminating on the same side of the spring and bent outwardly to form spaces I4 and I5 for interlocking engagement, as hereinafter described.

A connector [6 is formed for threaded engagement within the ends of the spring for connecting them together, preferably in end to end contact, as shown in Fig. 2. As illustrated, the connector I6 is formed by a spiral spring in the form of a closely wound helix having an external diameter slightly larger than the internal diameter of the spring ll so that it will snugly engage within the ends thereof. The coils of the helix forming the connector are wound in the same direction as the coils of the spring I I.

To join the ends of the spiral spring II and form an elastic band or ring, the connector is first threaded into one end l2 of the spring. The other end [3 of the spring is then rotated a number of turns backward against its own tension whereupon the exposed end of the connector is engaged with it and the spring released. This allows the end I3 to be rotated and returned to its normal position and in so doing it is threaded onto the end of the connector. The ends of the spring are threaded onto the connector a sufficient distance to cause the end 12 to engage in the space I5 of the other end and interlock therewith while the end l3 engages in the space I4, as shown in Fig. 2. The spaces l4 and I5 are formed, as'shown, by offsetting the ends I2 and I3, respectively, from the adjacent turns of the helix.

As illustrated in Fig. 3, the connector I! is formed from wire having a somewhat greater diameter than the wire forming the spring H. This provides a thread on the connector of greater pitch, but the same inclination, as the thread of the spring ends. As a result, when one end of the spring H is threaded on the connector, the helix thereof is elongated and the turns spread apart, while the other end is also elongated and interlocks therewith in the manner illustrated. In Fig. 3, the end of the spring H threaded on the connector I! from the right has been shown in solid black, in section, while that threaded on from the left has been shown in conventional cross-sectioning, for purposes of clarity.

In Fig. 4 is shown the manner of employing the annular helices in connection with a blank for either a transmission or recording of a message. The blank [8 is wrapped about a drum I9 with the edges overlapping, and helices II are slipped over the ends of the drum about the paper [8. If desired, an intermediate helix may also be employed, as shown. The drum [9 is then placed between revolving centers of a transmitting or receiving machine and rotated in the direction of the arrow. During rotation of the drum, the transmitting or receiving carriage 2i is moved longitudinally of the drum so as to scan the surface thereof. In the case of a transmitted message, the surface is scanned by means of a light beam and the reflected light utilized to energize a photoelectric cell through the conduits 22 and 23, In the case of a recording blank, the message is recorded thereon by means of a stylus 24 contacting with the surface of the blank in such manner that current may be passed from the stylus through the blank to a metallic cylinder IS. The helix II is adapted to be moved along the blank closely adjacent to the stylus 24 by means of a metal clip 25 carried by the carriage 2|. The intermediate helix is also moved along the blank as the carriage traverses the drum. The helices I I thus hold the paper in firm contact with the drum l9 at the point of engagement of the stylus therewith and thus materially assist in maintaining good electrical contact between the blank and the drum. If desired, the return path of the current passing through the blank may be, at least in part, through the left hand helix H, and the conductor 26. In this case a nonmetallic drum can be employed. It is extremely important that the overlapped edges of the blank be held firmly in engagement with the drum as this edge passes the stylus in order to ease the passage of the edge beneath the stylus and to prevent the possibility of tearing of the paper.

Due to the continuous nature of the spiral at the point of connection of the two ends, the rolling action of the spiral along the paper is greatly enhanced. There is thus no tendency for the elastic helix to drag over the surface of the paper with consequent scratching of the sensitized surface thereof. The rolling motion of the helix is smooth and continuous as distinguished from the tendency towards an intermittent or jerky rolling movement produced when the ends are joined through hooks in the usual manner. This jerky movement results from the fact that there is a resistance to rolling at the hooked joint which causes tension to be built up in the spiral until it becomes sufiic'ient to overcome the resistance to rolling at this point, whereupon the latter portion of the helix is given a sudden forward impetus as it rolls over.

It will be apparent that the invention provides an elastic metallic ring having a substantially continuous surface of constant diameter throughout. Various modifications and changes can be made in the structure shown without departing from the essential attributes of the invention, and we contemplate all such changes as coming within the scope of the appended claims.

What is claimed is:

1. In combination in a facsimile machine, a scanner, a cylindrical copyholding member and an elastic toroidal member for securing the copy to the outside of said copyholding member, said toroidal member being composed of a wire helix having its end convolutions secured together in tightly abutting relation.

2. In combination in a facsimile machine, a scanner, a cylindrical copyholding member and a helical spring in the form of an annulus, having its end convolutions secured together in overlapping abutting relation, for securing said copy to the outside of said copyholding member.

3. In combination in a facsimile machine, a scanner, a copyholding member and an elastic member for securing the copy to the outside of said copyholding member, said elastic member comprising a spiral spring, and a member threadedly engaging the opposite ends of said spring and holding the ends together in abutting relation to form an elastic ring.

4. In combination in a facsimile machine, a scanner, a copyholding member and an elastic member for securing the copy to the outside of said copyholding member, said elastic member comprising a spiral spring, and a threaded member having an external diameter slightly larger than the internal diameter of said spring and threadedly engaged within the opposite ends of said spring and holding said ends together in abutting relation to form an elastic ring.

5. In combination in a facsimile machine. a scanner, a copyholding member and an elastic member for securing the copy to the outside of said copyholding member, said elastic member comprising a spiral spring having each end turn thereof spaced from the adjacent turn, and a threaded member threaded within the opposite ends of said spring to form an elastic ring, said end turns being in interlocking engagement.

6. In combination in a facsimile machine, a scanner, a copyholding member and an elastic member for securing the copy to the outside of said copyholding member, said elastic member comprising a spiral spring having each and turn thereof spaced from the adjacent turn, and a connecting member formed by a spiral spring approximately equal in diameter to the internal diameter of said first spring and threaded within the opposite ends thereof to form an elastic ring, said end turns being in interlocking engagement.

'7. In combination in a facsimile machine, a scanner, a copyholding member and an elastic member for securing the copy to the outside of said copyholding member, said elastic member comprising a spiral spring, and a threaded member having threads of greater pitch than the threads formed by the spirals of said spring, threaded into each end of said spring a distance sufiicient to cause said spirals to interlock with each other.

RALEIGH J. WISE. ROBERT D. PARROTT. 

